AT&T 6300 Programmer's Manual page 127

Graphics
Line 25 is usually reserved as a "soft key"
display (see KEY statement in the Reference
section).
Multiple Display Page
A special feature of Text Mode is multiple
display pages. Your system has a 16K-byte
screen buffer, of which only 2K is required for
Text Mode (or 4K for 80 column width). The
buffer is therefore divided into different pages,
which can be written to and/or displayed
individually. There are 8 display pages in 40
column width and 4 display pages in 80 column
width.
Statements, Commands and Functions
The statements, commands and functions
available in Text Mode to display text are:
Statements/
Commands
CLS
COLOR (Text)
LOCATE (Text)
PRINT
PRINT USING
SCREEN
WIDTH
WRITE
Functions
CSRLIN
POS
SCREEN
SPC
TAB
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